Prefer stpcpy to strcat

* admin/merge-gnulib (GNULIB_MODULES): Add stpcpy.
* lib/gnulib.mk, m4/gnulib-comp.m4: Regenerate.
* lib/stpcpy.c, m4/stpcpy.m4: New files, from gnulib.
* lib-src/ebrowse.c (sym_scope_1, operator_name, open_file):
* lib-src/emacsclient.c (get_server_config, set_local_socket)
(start_daemon_and_retry_set_socket):
* lib-src/etags.c (main, C_entries, relative_filename):
* lib-src/pop.c (sendline):
* lib-src/update-game-score.c (main):
* lwlib/xlwmenu.c (resource_widget_value):
* src/callproc.c (child_setup):
* src/dbusbind.c (xd_signature_cat):
* src/doc.c (get_doc_string, Fsnarf_documentation):
* src/editfns.c (Fuser_full_name):
* src/frame.c (xrdb_get_resource):
* src/gtkutil.c (xg_get_file_with_chooser):
* src/tparam.c (tparam1):
* src/xfns.c (xic_create_fontsetname):
* src/xrdb.c (gethomedir, get_user_db, get_environ_db):
* src/xsmfns.c (smc_save_yourself_CB):
Rewrite to avoid the need for strcat, typically by using stpcpy
and/or lispstpcpy.  strcat tends to be part of O(N**2) algorithms.
* src/doc.c (sibling_etc):
* src/xrdb.c (xdefaults):
Now a top-level static constant.

1 files changed, 25 insertions, 0 deletions

diff --git a/m4/stpcpy.m4 b/m4/stpcpy.m4
new file mode 100644
index 00000000000..966ba951f52
--- /dev/null
+++ b/m4/stpcpy.m4
@@ -0,0 +1,25 @@
+# stpcpy.m4 serial 8
+dnl Copyright (C) 2002, 2007, 2009-2014 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+AC_DEFUN([gl_FUNC_STPCPY],
+[
+  dnl Persuade glibc <string.h> to declare stpcpy().
+  AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
+
+  dnl The stpcpy() declaration in lib/string.in.h uses 'restrict'.
+  AC_REQUIRE([AC_C_RESTRICT])
+
+  AC_REQUIRE([gl_HEADER_STRING_H_DEFAULTS])
+  AC_CHECK_FUNCS([stpcpy])
+  if test $ac_cv_func_stpcpy = no; then
+    HAVE_STPCPY=0
+  fi
+])
+
+# Prerequisites of lib/stpcpy.c.
+AC_DEFUN([gl_PREREQ_STPCPY], [
+  :
+])